Test collection sidebar responsiveness (#16896)

frontend/test/metabase/scenarios/collections/collections-sidebar.cy.spec.js

+import { restore, sidebar } from "__support__/e2e/cypress";
+
+describe("collections sidebar (metabase#15006)", () => {
+  beforeEach(() => {
+    restore();
+    cy.signInAsAdmin();
+
+    cy.visit("/collection/root");
+  });
+
+  it("should be able to toggle collections sidebar when switched to mobile screen size", () => {
+    cy.icon("close").should("not.be.visible");
+    cy.icon("burger").should("not.be.visible");
+
+    // resize window to mobile form factor
+    cy.viewport(480, 800);
+
+    sidebar().should("not.be.visible");
+
+    cy.icon("burger").click();
+    cy.icon("burger").should("not.be.visible");
+
+    sidebar().within(() => {
+      cy.findByText("First collection");
+      cy.icon("close").click();
+    });
+
+    cy.icon("burger");
+  });
+});